1. Introduction
It is a fact supported by many researchers that fractional calculus (FC) establishes a flexible extension for the classical one to arbitrary orders. FC has attracted particular attention from many researchers of mathematics, applied sciences, and engineering because of the various important applications of this field in modeling certain scientific phenomena and complex physical systems. Modeling systems using fractional derivatives can provide a good interpretation of the physical behavior of the studied systems due to the nonlocality and memory effects that have been exhibited in some systems. Some studies have been conducted on the mathematical analysis of FC and its applications such as European option pricing models [
1], p-Laplacian nonperiodic nonlinear boundary value problem [
2], nonlocal Cauchy problem [
3], economic models involving time fractal [
4], complex integral [
5], incompressible second-grade fluid models [
6], complex-valued functions of a real variable [
7], and separated homotopy method [
8]. Likewise, quantum calculus is a corresponding field of the standard infinitesimal one without the concept of limits. In spite of the long history that they already have, both theories are in the field of mathematical analysis, the investigation of their properties has emerged not so long ago. The quantum fractional calculus (q-fractional calculus), considered as the fractional correspondence of the q-calculus, was initially proposed by Jackson [
9,
10,
11]. Researchers such as Al-Salam [
12] and Agarwal [
13] gave a great boost to the fractional q-calculus and obtained important theoretical results. Based on these results, the fractional q-calculus has emerged as an instrument with great potential in the field of applications [
14,
15,
16,
17]. Even in recent years, many articles have been appeared on quantum integro-difference boundary value problems (BVPs), which are valuable abstract tools for modeling many phenomena in various fields of science [
18,
19,
20,
21,
22,
23,
24,
25,
26,
27,
28,
29,
30].
Asawasamrit et al. [
31] provided a multi-term q-integro-difference equation subject to nonlocal multi-quantum integral conditions displayed as
where
,
,
,
and
. The approach implemented by them to arrive at the existence property of solutions for the suggested q-BVP is based on the fixed-point techniques [
31]. After that in 2015, Etemad, Ettefagh and Rezapour [
32] concerned the three-term q-difference FBVP
with four-point q-integro-difference conditions
where
,
,
,
,
and
with
. Ntouyas and Samei [
33] turned to studying the solutions’ existence for the q-integro-difference FBVP
via boundary conditions
and
, in which
,
,
,
with
,
,
are defined by the rule
for
and
is assumed to be continuous with respect to all
variables [
33].
Stimulated by the above research studies, the following proposed nonlinear Caputo fractional quantum BVP is furnished with the fractional quantum integro-conditions:
along with its inclusion version given by
where
,
,
and
. Two operators
and
represent the Caputo quantum derivative (CpQD) and the Riemann-Liouville quantum integral (RLQI). Furthermore, continuous single-valued function
and multi-valued function
are assumed to be arbitrary equipped with some required specifications that will be explained subsequently. In comparison to other researches on the quantum difference BVPs that were published in the literature, we here deal with two abstract and extended structures of new fractional quantum difference equations/inclusions via q-integro-difference conditions in which the existing property of the relevant solutions is derived by terms of new notions of the functional analysis such as the condensing maps and the measure of noncompactness and the approximate endpoint criterion. These procedures on the suggested q-difference-BVPs (
1) and (
2) have been implemented in a limited range of research studies on the quantum fractional modelings. This yields the novelty and our main motivation to finalize this manuscript.
This research scheme is outlined as follows: We present the main concepts of the quantum calculus in
Section 2. Our main results caused by new fixed-point approaches about solutions’ existence of quantum BVP (
1) and (
2) will be obtained in
Section 3. In
Section 4, two numerical examples will be provided to support and validate our obtained results. A conclusion about our research work will be stated in
Section 5.
2. Fundamental Preliminaries
In this section, some important issues in the sense of q-calculus are discussed. We suppose that
. On the function
given for
, its q-analogue is defined by
, and
so that
and
[
17]. Now,
is a constant which is assumed to be contained in
. Let us now display the follwoing q-analogue of the existing power mapping
in a q-fractional settings:
for
. We note that by having
, an equality
is obtained immediately [
17]. For the given real number
, a q-number
is expressed as:
The q-Gamma function is illustrated using the following format:
so that
[
9,
17]. It is notable that
is valid [
9]. A pseudo-code inspired by (
3) and (
4) is proposed in Algorithm 1 for computing various Gamma function’s values in the proposed quantum settings.
Given a real-valued continuous function
ℏ, the quantum derivative of this function can be formulated by:
and also
[
34]. Given a function
ℏ, the quantum derivative of this function can be extended to an arbitrary higher order by
for any
[
34]. Obviously, we notice that
. Similarly, for computing this kind of q-derivative of
ℏ, in Algorithm 2, we propose a pseudo-code inspired by (
5).
Algorithm 1. Pseudo-code for : |
Require: |
- 1:
- 2:
for to n do - 3:
- 4:
end for - 5:
|
Ensure: |
Algorithm 2. Pseudo-code for : |
Require:, , r |
- 1:
- 2:
ifthen - 3:
- 4:
else - 5:
- 6:
end if
|
Ensure: |
Given continuous map
, the quantum integral of this function can be expressed as:
provided the absolute convergence of the existing series holds [
34]. The quantum integral of
ℏ can be similarly extended like quantum derivative to an arbitrary higher order using an iterative rule
for all
[
34]. Moreover, it is clear to note that
. A pseudo-code caused by (
6) is proposed in in Algorithm 3. We now suppose that
. This time, the similar q-operator of
ℏ from
to
can be defined in this case as follows:
when the series exists [
34]. A proposed pseudo-code caused by (
7) is organized in Algorithm 4 for such a purpose.
If we assume that a function
ℏ is continuous at
, then
is obtained [
34]. Moreover, the equality
holds for each
r. By considering a real number
in this case such that
, i.e.,
, for given function
, the RLQI of
ℏ is introduced by:
provided that the above value is finite and
[
35,
36]. Further, the semi-group specification for the mentioned q-operator occurs such that
for
[
35]. For
,
It is evident that if we take
, then
for any
. Given a function
, the CpQD for this function is formulated by:
if the integral exists [
35,
36]. The following property is valid:
It is evident that
for any
. For instance, by letting
,
and
, we have
In this direction, the graph of the CpQD for the function
for
is available in
Figure 1.
Algorithm 3. Pseudo-code for : |
Require:, n, , r, |
- 1:
- 2:
for to n do - 3:
- 4:
- 5:
end for - 6:
|
Ensure: |
Algorithm 4. Pseudo-code for : |
Require:, , k, , |
- 1:
- 2:
fordo - 3:
- 4:
end for - 5:
|
Ensure: |
Lemma 1 ([
37])
. Assume that and . Then, we have: According to the above lemma, the given fractional quantum differential equation,
, has a general solution which is obtained by
so that
, and
[
37]. It is worth noting that for each continuous
ℏ, according to Lemma 1, we get:
where
illustrate constants contained in
, and
[
37].
Next, we recall some essential inequalities and concepts. The Kuratowski measure of noncompactness
is defined by
where
and
is bounded subset of Banach space
. Moreover, it is identified that
[
38].
Lemma 2 ([
38])
. Consider the bounded subsets and of an arbitrary real Banach space . Then, the following conditions hold: ;
are the closure and convex hull of ;
if ;
;
;
;
.
Lemma 3 ([
39])
. Regard as a Banach space. Then, for each bounded set , a countable set exists subject to . Lemma 4 ([
38])
. Regard as a Banach space. Let be bounded and equi-continuous set contained in . Then, is continuous on , and we have . Lemma 5 ([
38])
. Let be a Banach space. Let be bounded and countable set. Then, is Lebesgue integrable on , and we have: Definition 1 ([
38]).
Regard as a Banach space and as a bounded and continuous operator. Then, the map is termed condensing if for any bounded closed set , the inequality holds. Theorem 1 ([
38], Sadovskii’s fixed point theorem).
Regard as a Banach space. Let be a bounded, closed and convex set contained in . Furthermore, assume that continuous mapping is condensing. Then, there exists at least one fixed point for the map in . Let us denote the normed space by . Regard and as a family of all non-empty, all bounded, all closed, all compact and all convex sets contained in , respectively.
Definition 2 ([
40]).
An element is termed an endpoint of a multi-valued function whenever we get . The multi-valued map
has an approximate endpoint criterion (AEPC) if
Ref. [
40]. Next, a required theorem related to the proposed quantum boundary problem is recalled.
Theorem 2 ([
40], Endpoint theorem)
. Let’s assume that is a complete metric space, and is u.s.c subject to for each , , and . Assume that is a multi-valued map such that for each , the following inequality holds:Then, there is exactly one endpoint for iff has an approximate endpoint criterion.
3. Main Results
We regard the family of continuous functions on
by
and the defined sup-norm
, for all members
, confirms that the space
becomes a Banach space. In the sequel, we will establish the existence results for quantum BVP (
1) and (
2). Before moving to the existence results, the following proposition will play an essential role:
Proposition 1. Let , , , , and . Then, the function satisfies as a solution for the given quantum integro-difference FBVP (CpQFP) formulated by iff is a solution for the fractional quantum integral (FQI) equation given by Proof. Firstly, the given function
is regarded as a solution for (
8). By virtue of
, taking the integral in the RL-settings of order
to (
8), we arrive at
so that
are some constants that are needed to be obtained. By considering
, the following immediate results are obtained
Now, by virtue of the given boundary conditions, we get
and
where we regard the constants
along with the functions with respect to
r as
By substituting the values of
,
and
in (
11), integral solution (
9) is obtained. The converse part can be easily deduced. □
Remark 1. Note that for simplicity in the subsequent computations, we set the following upper bounds by virtue of the functions displayed in (12): Theorem 3. Let be continuous. In addition, assume that there exists a continuous along with a nondecreasing continuous map such that for each and , We suppose that there exists a function such that for each bounded set and , Then, at least one solution of the given Caputo fractional quantum BVP (1) exists on if where .
Proof. Introduce the mapping
defined as:
where
and is classified as a convex bounded closed space. Obviously, the fixed point of the proposed operator
is the quantum fractional BVP’s solution (
1).
Firstly, we verify the continuity of
on
. Take the sequence
in
such that
for each
. Since
is continuous on
, so we can write
. Now, with the aid of Lebesgue dominated convergence theorem, we obtain:
for each
. Thus, we get
. Hence, the continuity of
on
is proved. Now, we want to examine uniform boundedness of
on
. To accomplish this goal, consider
. In view of inequalities (
13) and (
14), we have:
Consequently, we can declare that
, and this implies uniform boundedness of
on
. Next, we ensure the equi-continuity of
. In order to check this, consider
such that
and
. Then, we get:
Note that the above inequality’s right hand side goes to zero as (independent of ℏ). Hence, it is evident that as , and this confirms that is an equi-continuous. Consequently, we conclude that is a compact operator on in view of the famous Arzela–Ascoli theorem.
At this point, we will check that
is condensing operator on
. By Lemma 3, it is obvious that a countable set
exists for each bounded subset
such that
holds. Hence, in the light of Lemmas 2, 4 and 5, the following is obtained
By applying condition (
16), we get
. This clearly implies that
is condensing operator on
. Ultimately, by employing Theorem 1, we can infer that the map
possesses one fixed point leastwise in
. Thus, it is found at least one solution for the supposed quantum-integro-difference FBVP (
1) and finally the proof process is terminated. □
Now, we set up an existence criterion for the given fractional quantum inclusion BVP (
2). The inclusion problem’s solution (
2) is determined by an absolutely continuous function
whenever it satisfies the given fractional quantum integro-difference conditions, and a function
exists such that the inclusion
holds for almost all
, and we have:
for each
. Let
represents the collection of all selections of
for each
and is defined as
Construct a multi-valued map
which is defined as
where
Theorem 4. Let be a multi-valued map. Suppose that
an increasing u.s.c map exists such that , and for every ;
is integrable and bounded and is measurable for every ;
exists subject to for each and , where and the multi-valued map formulated in (21) satisfies approximate endpoint criterion.
Then, a solution is found for the given quantum-difference inclusion FBVP (2).
Proof. We are going to determine that an endpoint exists for the multifunction
given by (
21). Since the map
is measurable and closed-valued set-valued mappingl therefore, it has a measurable selection. As a result,
. Firstly, we show that
is closed for every
. Consider the sequence
in
such that
converges to
ℏ. For each n, there exists
such that
for almost all
. Since the multi-valued function
is compact, we have a subsequence
converging to
. Thus,
and
for almost all
. This indicates that
and therefore,
is closed-valued. Since
is compact multi-valued function, it is simple to check that
is bounded for all
. At last, we prove that
holds. Let
and
. Select
such that
for all
. Since
for each
, so there exists
such that
for each
. Now, the multi-valued map
is considered, which is characterized by
Since
and
are measurable, so it is obvious that the multifunction
is measurable. Now, select
such that
for all
. Choose
such that
for any
. Then, we get
Thus, we get
. Hence,
for each
. By utilizing
, we realize that
has Theorem 2, a member
exists such that
. This indicates that
is the solution of the fractional quantum-difference inclusion problem (
2), hence, our proof is finally completed. □